U.S. patent number 7,555,202 [Application Number 10/207,845] was granted by the patent office on 2009-06-30 for digital dat recording/reproducing apparatus.
This patent grant is currently assigned to Pioneer Electronic Corporation. Invention is credited to Hidehiro Ishii, Tadashi Noguchi, Akihiro Tozaki.
United States Patent |
7,555,202 |
Noguchi , et al. |
June 30, 2009 |
Digital dat recording/reproducing apparatus
Abstract
A digital data recording/reproducing apparatus which divides
each of information data pieces into a plurality of cells, further
divides each of the cells into a series of a plurality of units,
and records the units. The digital data recording/reproducing
apparatus has means for recording a required time for reproduction
until the head position of a unit is reached, with reference to the
head position of an information data cell to which a cell belongs,
as a unit start time, in addition to each of the units, and means
for recording a cell start time (T.sub.s) equal to a required time
for reproduction until the head position of each of the cells is
reached, and a required time for reproduction (P.sub.s) of each of
the cells in a management data region.
Inventors: |
Noguchi; Tadashi (Tokorozawa,
JP), Tozaki; Akihiro (Tsurugashima, JP),
Ishii; Hidehiro (Tokorozawa, JP) |
Assignee: |
Pioneer Electronic Corporation
(Tokyo, JP)
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Family
ID: |
13469263 |
Appl.
No.: |
10/207,845 |
Filed: |
July 31, 2002 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20020176701 A1 |
Nov 28, 2002 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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09271989 |
Mar 19, 1999 |
6445873 |
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Foreign Application Priority Data
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Mar 20, 1998 [JP] |
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10-71741 |
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Current U.S.
Class: |
386/278; 360/18;
360/32; 386/248; 386/286; 386/326; 386/353 |
Current CPC
Class: |
G11B
27/105 (20130101); G11B 27/11 (20130101); G11B
27/3027 (20130101); G11B 27/329 (20130101); H04N
9/8042 (20130101); G11B 27/34 (20130101); G11B
2220/216 (20130101); G11B 2220/2562 (20130101); G11B
2220/65 (20130101); H04N 5/85 (20130101) |
Current International
Class: |
H04N
7/00 (20060101) |
Field of
Search: |
;386/104,95,96-97,46,124-126,106,110,69,105,111-112,52,33,27,70,18,32 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 797 205 |
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Sep 1997 |
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EP |
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0 814 475 |
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Dec 1997 |
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EP |
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0 903 743 |
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Mar 1999 |
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EP |
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0 903 744 |
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Mar 1999 |
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EP |
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0 929 072 |
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Jul 1999 |
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EP |
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0 942 426 |
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Sep 1999 |
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EP |
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1 035 546 |
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Sep 2000 |
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EP |
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00/30112 |
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May 2000 |
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WO |
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00/30113 |
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May 2000 |
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WO |
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Primary Examiner: Tran; Thai
Assistant Examiner: Atala; Jamie Jo
Attorney, Agent or Firm: Drinker Biddle & Reath LLP
Parent Case Text
This is a continuation of application Ser. No. 09/271,989 filed on
Mar. 19, 1999 now U.S. Pat. No. 6,445,873.
Claims
What is claimed is:
1. A recording signal generating apparatus for receiving an
information data piece and management data relating to said
information data piece to generate a data signal to be recorded on
a recording medium, said information data piece comprising a
plurality of data cells, said management data including cell
reproduction time periods of said plurality of data cells,
comprising: a divider for dividing said plurality of data cells
into a series of data units in accordance with a predetermined data
format; a first calculator for calculating unit start timings for
the respective data units, each of the unit start timings
representing a time period required for reproduction of data from a
head position of said information data piece up to a head position
of each of the data units, a second calculator for calculating cell
start timings for the respective data cells using the cell
reproduction time periods, each of the cell start timings
representing a time period required for reproduction of data from a
head position of said information data piece up to a head position
of each of the data cells, a first modifier for modifying said
information data piece by adding each of data pieces which
represent the respective unit start timings to the corresponding
data unit in accordance with the predetermined data format to
generate a modified information data piece; a second modifier for
modifying said management data by inserting data representing the
cell start timings into said management data in accordance with the
predetermined data format to generate modified management data; and
a generator for combining said modified information data piece and
said modified management data to generate a data signal to be
recorded on said recording medium.
2. A recording signal generating apparatus according to claim 1,
further comprising: a receiver for receiving a cell division
instruction which specifies one of the data units in one of said
plurality of data cells and instructs to divide said one of said
plurality of data cells; and an editor, in response to said cell
division instruction, for dividing said one of said plurality of
data cells in two to edit said modified management data by
inserting therein the unit start timing of a specified unit as a
cell start timing.
3. A recording signal generating apparatus according to claim 1,
further comprising: a memory for storing the reproduction time
periods for said plurality of data cells and the cell start
timings; a third calculator for receiving an indication indicating
a unit start timing of a unit which is under reproduction to
calculate a reproduction elapsed time using the indicated unit
start timing, stored reproduction time periods for said plurality
of data cells and stored cell start timings.
4. A method for generating a data signal to be recorded on a
recording medium, comprising the steps of: receiving an information
data piece and management data relating to said information data
piece, said information data piece comprising a plurality of data
cells, said management data including cell reproduction time
periods of said plurality of data cells; dividing said plurality of
data cells into a series of data units in accordance with a
predetermined data format; calculating unit start timings for the
respective data units, each of the unit start timings representing
a time period required for reproduction of data from a head
position of said information data piece up to a head position of
each of the data units, calculating cell start timings for the
respective data cells using the cell reproduction time periods,
each of the cell start timings representing a time period required
for reproduction of data from a head position of said information
data piece up to a head position of each of the data cells,
modifying said information data piece by adding each of data pieces
which represent the respective unit start timings to the
corresponding data unit in accordance with the predetermined data
format to generate a modified information data piece; modifying
said management data by inserting data representing the cell start
timings into said management data in accordance with the
predetermined data format to generate modified management data; and
combining said modified information wherein the steps of receiving,
dividing, calculating unit start timings, calculating cell start
timings, modifying, and combining are performed by a controller
data piece and said modified management data to generate a data
signal to be recorded on said recording medium.
5. A method for generating a recording signal according to claim 4,
further comprising the steps of: receiving a cell division
instruction which specifies one of the data units in one of said
plurality of data cells and instructs to divide said one of said
plurality of data cells; and dividing, in response to said cell
division instruction, said one of said plurality of data cells in
two to edit said modified management data by inserting therein the
unit start timing of a specified unit as a cell start timing.
6. A method for generating a recording signal according to claim 4,
further comprising the steps of: storing the reproduction time
periods for said plurality of data cells and the cell start
timings; receiving an indication indicating a unit start timing of
a unit which is under reproduction; and calculating a reproduction
elapsed time using the indicated unit start timing, stored
reproduction time periods for said plurality of data cells and
stored cell start timings.
7. A method for recording information data on a recording medium,
the recording medium having an information data area and a
management data area, comprising the step of: recording information
data in the information data area, determining whether or not
attribute data of the information data is included in the existing
management data in the management data area, the attribute data
indicating the reproduction scheme for the information data, and
recording the management data in addition to the existing
management data, when it is determined that the attribute data of
the information is not included in the recorded data in the
management data area; and overwriting wherein the steps of
recording, determining, and overwriting data are performed by a
controller the management data including attribute data identical
to the attribute data of the information data when it is determined
that the attribute data of the information data is included in the
existing management data.
8. A recording apparatus for recording information data on a
recording medium, the recording medium having first information
data and first management data for reproducing the first
information data, the apparatus comprising: a recording device
which records second information data, and a controller, wherein
the controller determines whether or not the second data has an
attribute identical to an attribute of the first information data,
wherein if the second information data has the identical attribute,
the controller controls the recording device so as to overwrite the
first management data, if the second information data has a
different attribute from the attribute of the first information
data, the controller creates second management data and controls
the recording device so as to record the second management
data.
9. A recording apparatus according to claim 8, wherein the first
and second management data are recorded in a management data
area.
10. A recording apparatus according to claim 8, wherein the first
and second information data are recorded in an information data
area.
11. A recording method for recording information data on a
recording medium, the recording medium having first information
data and first management data for reproducing the first
information data, the method comprising: recording second
information data, and determining whether or not the second data
has an attribute identical to an attribute of the first information
data, wherein if the second information data has the identical
attribute, overwriting the first management data, if the second
information data has a different attribute wherein the steps of
recording, determining are performed by a controller from the
attribute of the first information data, creating second management
data and recording the second management data.
12. A recording method according to claim 11, wherein the first and
second management data are recorded in a management data area.
13. A recording method according to claim 11, wherein the first and
second information data are recorded in an information data area.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a digital data
recording/reproducing apparatus, and more particularly to a digital
data recording/reproducing apparatus for recording/reproducing
digital data compressed in accordance with a variable bit rate
encoding scheme.
2. Description of Related Background Art
At present, widespread video and audio media include a laser disk
(LD), a VHS video and so on in the analog scheme, and a mini-disk
(MD), a compact disc (CD) and so on in the digital scheme. On the
other hand, as package media for the next generation, technological
developments have been vigorously advanced for practical use of a
rewritable digital versatile disk (DVD-R/W) which enables recording
and reproduction of images and sound with high quality for a long
time. In a recording method using DVD-R/W, information data pieces
such as a movie, audio and so on can be recorded on a disk in high
density. Image data are recorded/reproduced in accordance with a
highly efficient encoding scheme such as MPEG2, while audio data
are recorded/reproduced in accordance with compression schemes such
as PCM, AC3 or the like. In the following, a collection of data
such as a full program, a full movie or the like is called an
"information data piece", and data which includes one or a
plurality of information data piece is called an "information data
group".
In a recording/reproducing scheme for a conventional recordable and
erasable digital data recording/reproducing apparatus, for example,
MD, an audio information data piece is again divided into a
plurality of subpieces, each of which is given address information
that is relied on to display a playing time and to search for
particular data. Stated another way, since MD has a fixed
compression ratio for audio data, an actually required time for
reproduction can be unitarily calculated by multiplying the amount
of data by a playing time per unit time. Therefore, a data region
is comprised only of audio data and does not include time
information on reproduction.
However, as a method of extending a recording time for images,
DVD-R/W has employed a "variable bit rate coding: VBR" which
changes the amount of codes in accordance with a change in the
amount of information in an image in place of a conventional
"constant bit rate coding: CBR", so that an actually required time
for reproduction cannot be calculated directly from the amount of
compressed data. In other words, it is not possible to use a
conventional approach of deriving a playing time from the address
of a reproduced position. Also, while DVD-R/W has a feature of
providing an erasable recording medium, recorded time information
becomes discontinuous if the user erases a desired region or the
like, thereby causing impediments to a time search, a playing time
display, and so on.
OBJECT AND SUMMARY OF THE INVENTION
As described above, when digital data compressed using a variable
bit rate coding is recorded/reproduced, a time required for
reproduction cannot be derived directly from the address of a
reproduced position, thereby giving rise to a problem that a time
search, a playing time display, and-so on are prevented. The
present invention has been made in view of the problem as
mentioned, and its object is to provide a digital data
recording/reproducing apparatus which is capable of deriving
playing-time information even on a midway position of information
data that has undergone editing such as chapter setting, erasure or
the like after recording, when such information data is reproduced
from the midway position.
To achieve the above object, the present invention provides a
digital data recording/reproducing apparatus for dividing each of
information data pieces into a plurality of segments to
sequentially record the segments in an information data region on a
recording medium, additionally recording a plurality of management
data corresponding to each of one or a plurality of information
data groups each including one or a plurality of the information
data pieces, in a management data region on the recording medium,
and reproducing the information data pieces on the basis of the
management data. The digital data recording/reproducing apparatus
comprises means for dividing each of the segments into a series of
a plurality of units, and recording a required time for
reproduction from a head position of an information data piece, to
which the segment belongs, to a head position of each of the units
as a unit start time in addition to each of the units, and means
for recording a segment start time (T.sub.s) equal to a required
time for reproduction from a head position of an information data
piece, to which the segments belong, to ahead position of each of
the segments, and a required time for reproduction (P.sub.s) of
each of the segments in the management data region.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating the configuration of a
digital data recording/reproducing apparatus according to the
present invention;
FIG. 2 is a schematic diagram for explaining the structure of data
which is recorded on a disk;
FIG. 3 is a schematic diagram for explaining the structure of data
and time information which are recorded on a disk according to the
present invention;
FIG. 4 is a schematic diagram showing a data structure and
recording regions according to the present invention;
FIG. 5 is a table showing attribute information data according to
the present invention;
FIG. 6 is a flow chart illustrating a procedure for a recording
operation processing routine according to the present
invention;
FIG. 7 is a flow chart illustrating a procedure for a reproducing
operation processing routine according to the present
invention;
FIG. 8 is a flow chart illustrating a procedure for a cell division
processing routine according to the present invention;
FIG. 9 is a flow chart illustrating a procedure for a cell erasure
processing routine according to the present invention;
FIG. 10 is a flow chart illustrating a procedure for a playing time
calculation routine according to the present invention; and
FIG. 11 is a flow chart illustrating a procedure for a time search
routine according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention will hereinafter be
described in detail with reference to the accompanying
drawings.
FIG. 1 illustrates the configuration of a digital data
recording/reproducing apparatus according to the present
invention.
The digital data recording/reproducing apparatus in FIG. 1 is
provided with an analog audio signal and video signal, for example,
from a television tuner or the like as a source. An input audio
signal is converted to a digital form by an A/D converter 2, and
supplied to an audio encoder 3, while a video signal is converted
to a digital form by an A/D converter 4 and supplied to a video
encoder 5.
The audio encoder 3 applies a predetermined code conversion (for
example, data compression processing) to a digital audio signal,
and supplies its code converted output to a first input of a
multiplexer 8. The video encoder 5 applies a predetermined code
conversion (for example, compress processing) to a digital video
signal, and supplies its code converted output to a second input of
the multiplexer 8. The multiplexer 8 is also supplied at a third
input thereof with an management data signal produced by a system
control circuit 10. The multiplexer 8 time-division-multiplexes the
first, second and third input signals to produce a multiplexed
information signal composed of the audio and video information data
signals and the management data signal.
The multiplexed information signal is supplied to a
recording/reproducing control circuit 15 and recorded on a
rewritable recording medium such as a rewritable DVD-R/W or the
like.
In a reproducing mode for reproducing recorded information on a
recording medium 17, the recording/reproducing control circuit 15
supplies a multiplexed information signal read by a
recording/reproducing head 19 to a demultiplexer 22. The
demultiplexer 22 time-division-demultiplexes the multiplexed
information signal supplied thereto to separately output an audio
signal, a video signal and a management data signal equivalent to
those at the respective inputs of the multiplexer 8.
An audio signal output from the demultiplexer 22 is supplied to an
audio decoder 23 which applies the audio signal with conversion
processing reverse to the code conversion performed in the encoder
3 (for example, decompression processing). The reversely converted
output is further converted to an analog form by a D/A converter 24
and delivered as an analog audio output. A video signal output from
the demultiplexer 22 is supplied to a video decoder 25 which
applies the video signal with a conversion processing reverse to
the code conversion performed in the encoder 5 (for example,
decompression processing). The reversely converted output is
converted to an analog form by a D/A converter 26 and delivered as
an analog video output.
In a recording mode for recording audio and video signals, a
recording/reproducing head 19 writes a multiplexed information
signal into a recording medium 17 in a predetermined format under
the control of the recording/reproducing control circuit 15 which
follows instructions from the system control circuit 10. In this
event, the multiplexed information signal is also supplied to the
demultiplexer 22. The flow of signal processing in successive
components including the demultiplexer 22 subsequent to the
recording/reproducing control circuit 15 in the recording mode is
similar to the foregoing.
A recording medium 17 loaded into the recording/reproducing
apparatus of the present invention may be a recording medium which
permits overwriting of information previously recorded thereon,
other than the aforementioned DVD-R/W.
The system control circuit 10 also issues instruction signals for
controlling a read operation and a write operation to the
recording/reproducing control circuit 15. Any of these instruction
signals includes address information indicative of an actually
recorded position or a region on a loaded recording medium. With
the address information, information can be written at an arbitrary
recording position on the recording medium, and information can be
read from an arbitrary recorded position. Briefly, the system
control circuit 10 performs an address control for accessing an
arbitrary recorded position on a recording medium in the
reproduction and recording modes for reproducing and recording
information from and on the recording medium.
The system control circuit 10 further controls other components in
response to instruction signals from a manipulation unit 30 serving
as a user interface unit. Representative ones of the instruction
signals include recording/reproducing instructions, and editing
instructions such as a chapter setting instruction or an erasure
instruction during a reproduction or recording operation.
Therefore, the manipulation unit 30 serves as change instruction
generating means for generating a change instruction in an editing
mode.
The system control circuit 10 can force associated components to
perform operations in accordance with the contents of manipulations
of the manipulation unit 30, using a memory 35 for storing data
indicative of the aforementioned recording/reproducing or edit
instruction, and data read from the recording medium 17.
While the foregoing description has been made for a digital data
recording/reproducing apparatus, taken as an example, which is
supplied with data from a television tuner or the like as a source,
the present invention is not limited to such a configuration.
Alternatively, the digital data recording/reproducing apparatus of
the invention may take a form in which external input terminals for
audio and video signals are provided for directly leading them to
the multiplexer 8, instead of providing a television tuner, A/D
converters 2, 4 and encoders 3, 5, such that these external input
terminals can be supplied with an audio digital signal and a video
digital signal which have previously undergone code conversions
such as those executed in the encoders 3, 5.
The system control circuit 10 and the recording/reproducing control
circuit 15 are commonly used as recording control means and
reproduction control means.
Next, the embodiment of the present invention will be described
with reference to the accompanying drawings.
FIG. 2 shows the structures of an information data group and
management data which are recorded on a recording medium. VMGI
stores disk common data associated with the information data group,
which is data for generally managing a disk, for example, menu data
or the like for a disk. Video Object Set (VOBS) is an information
data group which collects one or a plurality of Video Objects
(VOB), each of which is a set of information data pieces, for
example, a full program, a full movie or the like. Video Title Set
Information (VTSI) is management data associated with VOBS. BUP is
backup data for VTSI, and contains the same contents as VTSI. VOB
is further divided into a plurality of segments, each of which is
hereinafter called a "cell."
FIGS. 3 and 4 are schematic diagrams for explaining an example of a
data structure recorded on an optical disk which serves as a
recording medium in the digital data recording/reproducing
apparatus according to the present invention. In the present
invention, each of cells is divided into a series of plural units
as shown in FIG. 3, and a required time for reproduction
(t.sub.s,u) from the head position (time T=0) of an information
data piece, to which a cell belongs, to the head position of each
of the units is additionally recorded in the cell as a unit start
time. Further, a cell start time (T.sub.s) equal to a required time
for reproduction from the head position of an information data
piece, to which a cell belongs, to the head position of each of the
units, as well as the unit start time (t.sub.s,u) are recorded in
VTSI. A required time for reproduction (P.sub.s) of each of cells
is also recorded in VTSI.
In the present invention, when a plurality of information data
groups are recorded, respective management data VTSI #i (i=1,2, . .
. ) are collectively recorded at predetermined positions on the
disk, for example, in a management data region defined in an inner
peripheral region, as shown in FIG. 4. Also, backup data BUP #i
(i=1,2, . . . ) are similarly recorded in a recording region. In
this event, BUP #i is preferably recorded continuously to the
recording region for VTSI #i. Further, the disk common data VMGI is
also recorded in the management data region. For the management
data region, a sufficient recording region has been previously
reserved for recording a presumably maximum amounts of VTSI #i and
BUP #i. While information data groups are recorded in an
information data region, VOB need not be recorded in the order of
VTSI corresponding thereto, and empty regions may be included
therein.
In the present invention, the management data VTSI further includes
attribute information data indicative of a recording scheme for
each of the information data groups VOBS. The attribute information
data includes video display information such as an encoding scheme
for convenience of decoding, as well as a scanning speed, the
number of scanning lines, an aspect ratio and so on for convenience
of displaying reproduced data. For example, in an example shown in
FIG. 5, the attribute information data is classified into 12 modes.
The information data groups are recorded or reproduced on the basis
of the attribute information data, wherein the same kind of
attribute information data is preferably recorded in the same
VTSI.
In the following, recording and reproducing operations of the
digital data recording/reproducing apparatus, which is an
embodiment of the present invention, will be described with
reference to the flow charts shown in FIGS. 6-11.
FIG. 6 illustrates an example of a procedure for a recording
operation processing routine executed by the system control circuit
10. The system control circuit 10 fetches settings for a recording
instruction or the like such as a recording mode and a recording
time, entered by the user through the manipulation unit 30, from
the memory 35 (step 11). Then, the system control circuit 10 issues
an instruction to the recording/reproducing control circuit 15 to
record audio/video data (hereinafter called the "AV data") and unit
start times (t.sub.s,i, i=1,2, . . . ) in an empty region within
the information data region in a desired recording mode (step 12).
The system control circuit 10 determines whether or not an
interrupt instruction has been entered by the user through the
manipulation unit 30, such as a cell division instruction, i.e.,
chapter setting or the like (step 13). Continuing the description
with reference to FIG. 3, when an interrupt instruction has been
entered for chapter setting or the like, the system control unit 10
assigns the unit start time (t.sub.s,u) at the time the interrupt
instruction has been entered (assuming the time of a unit #u in a
cell #S) to a new cell start time (T.sub.s,2), and stores in the
memory 35 the new cell start time (T.sub.s,2) together with a
required time for reproduction (P.sub.s,l)of a newly created
preceding cell (units #1 to #u-1) after the division (step 14).
Next, the system control circuit 10 determines whether or not the
AV data has been recorded on the basis of the recording settings by
the user (step 15). If the AV data has been recorded, the recording
operation is terminated (step 16). Next, the system control circuit
10 fetches management data previously stored in the memory 35 from
the memory 35 (step 17). It should be noted that the digital data
recording/reproducing apparatus according to the embodiment reads
all management data recorded in a management data region of a disk
and stores them into the memory 35, when the disk was loaded
thereinto, such that the management data is managed on the memory
35 while the disk is loaded in the apparatus. Next, the system
control circuit 10 determines whether or not the attribute
information data of the recorded AV data has already been included
in the management data (step 18). If already included, VTSI
including the same attribute information data as that of the just
recorded AV data is overwritten by the management information (step
19). If the same attribute information data has not been included,
VTSI including the management data and the attribute information
data are newly recorded in addition to the existing VTSI (step 20),
followed by the completion of the recording operation
processing.
FIG. 7 illustrates an example of a procedure for a reproducing
operation processing routine executed by the system control circuit
10. The system control circuit 10 fetches settings for a desired
program to be reproduced or the like, entered by the user, from the
memory 35 (step 31). Next, the system control circuit 10 retrieves
management data previously read from a disk and stored in the
memory 35, when the disk was loaded, from the memory 35 (step 32),
and identifies a mode and management data associated with the
desired program to be reproduced from the retrieved management data
(step 33). Next, the system control circuit 10 issues an
instruction to the recording/reproducing control circuit 15 to
reproduce AV data associated with the desired program based on the
identified mode and management data (step 34). The system control
circuit 10 determines whether or not the AV data based on the
settings has been reproduced (step 35), and issues a reproduction
stop instruction if the AV data has been reproduced (step 36),
followed by the completion of the reproducing operation
processing.
FIG. 8 illustrates an example of a procedure for a cell division
processing routine for editing such as chapter setting, erasure or
the like. The system control circuit 10 calls are producing
routine, and instructs a disk reproducing operation (step 41).
Describing with additional reference to FIG. 3, when a cell
division signal is entered from the manipulation unit 30 during
reproduction, the system control circuit 10 fetches the signal
(step 42), and extracts a unit start time (t.sub.s,u) at that time
from the reproduced data (step 43). Next, the system control
circuit 10 fetches a required time for reproduction (P.sub.s) and a
cell start time (T.sub.s) of a cell, to which the unit belongs
before division, from the memory 35 in which such data read from a
disk have been stored when the disk was loaded (step 44). Next, the
system control circuit 10 calculates required times for
reproduction (denoted by P.sub.S,1, P.sub.S,2, respectively) of the
two divided cells from the foregoing three values (P.sub.s,
T.sub.s, t.sub.s,u) (step 45). Then, the system control circuit 10
deletes the required time for reproducing the cell (P.sub.s) and
the cell start time (T.sub.s) before the division from the memory
35 (step 46), and stores the required times for reproducing the
resultant cells (P.sub.s,1, P.sub.s,2) and cell start times
(denoted by T.sub.s,1, T.sub.s,2, respectively) in the memory 35
(step 47). The system control circuit 10 determines whether or not
the cell division processing has been terminated (step 48), and
repeats the flow from the fetching of signals (step 42) if not
terminated, and issues a reproduction stop instruction if the cell
division processing has been terminated (step 49). Then, the system
control circuit 10 issues an instruction to the
recording/reproducing control circuit 15 to record the management
data stored in the memory 35 in the management data region on the
disk (step 50), followed by the completion of the cell division
processing.
FIG. 9 illustrates an example of a procedure for a cell erasure
processing routine during editing. The system control circuit 10
fetches desired cell erasure settings entered by the user from the
memory 35 (step 61), and deletes a playing time and a cell start
time of a cell, which has been specified for erasure, from
management data on the memory 35 (step 62). Next, the system
control circuit 10 determines whether or not the specified cell has
been erased (step 63), and repeats the flow from the deletion of
data from the memory (step 62) if not erased, and issues an
instruction to the recording/reproducing control circuit 15 to
record the management data stored in the memory 35 in the
management data region on the disk (step 64) if erased, followed by
the completion of the cell erasure processing.
FIG. 10 illustrates an example of a procedure for a playing time
calculation routine for use by the system control circuit 10 during
are producing operation. The system control circuit 10 fetches a
required time for reproduction (P.sub.i) and a cell start time
(T.sub.i) of each of cells in an information data piece, which has
been specified for reproduction, from management data on the memory
35 (step 71). Then, the system control circuit 10 fetches a unit
start time (t.sub.s,u) of a unit under reproduction (step 72),
calculates the sum of a total sum of required times for
reproduction of cells preceding to the cell under reproduction
(.SIGMA.P.sub.i; i=1,2, . . . ,s-1) and the value derived by
subtracting a cell start time of the cell under reproduction from
the unit start time of the unit under reproduction
(t.sub.s,u-T.sub.s), and assigns the resultant value as a playing
time (step 73). Therefore, even if a cell preceding to the cell
under reproduction, for example, a cell #k (1<k<S) has been
already erased, a required time for reproduction (P.sub.k) of the
erased cell is not included in the sum (.SIGMA.P.sub.i) of the
required times for reproduction of the cells, thus making it
possible to correctly calculate a playing time. The playing-time
calculation processing is completed after executing the foregoing
steps.
FIG. 11 illustrates an example of a procedure for a time search
routine for searching for a reproduced position based on a playing
time. The system control circuit 10 fetches a desired reproduction
time from the memory 35 (step 81), and instructs the
recording/reproducing control circuit 15 to perform a reproducing
operation near the position corresponding to the desired
reproduction time (step 82). Next, the system control circuit 10
calls the playing-time calculation routine to calculate the playing
time at the current position from a unit start time (t.sub.s,u) of
a unit under reproduction, and makes a search such that the
calculated playing time is coincident with the desired reproduction
time (step 83). Then, the system control circuit 10 determines
whether or not the calculated playing time is equal to the set time
(step 84), and completes the time search processing at the time
they are equal.
As previously described above with reference to FIG. 3, according
to the present invention, by using a unit start time read from a
reproduced position, and a cell start time and a required time for
reproduction of a unit recorded on a recording medium and stored in
a memory, while relying on the head position of a information data
piece under reproduction as a reference time, it is possible to
realize a digital data recording/reproducing apparatus which is
capable of readily performing a calculation of a reproduction
elapsed time at an arbitrary reproduced position, a time search,
and so on even if an information data piece, which has undergone
editing such as chapter setting, erasure or the like after
recording, is to be reproduced from a midway position. Also, by
including attribute information data indicative of a reproducing
scheme for information data groups in management data, and
recording or reproducing the information data groups on the basis
of the attribute information data, one or a plurality of
information data groups having different attributes can be freely
processed for recording, reproduction, editing and so on. Further,
by collectively recording the management data in a predetermined
management data region and continuously recording information data
groups having different attributes in a predetermined information
data region, a recording region is free from blank invalid regions,
and a longer recording time can be achieved.
While the foregoing embodiment has been described for a
recording/reproducing apparatus which handles DVD-R/W, the present
invention can be applied to apparatus which handle other kinds of
recording disk media, and storage devices such as a semiconductor
memory or the like.
As described above in detail, according to the present invention,
when compressed digital data is recorded/reproduced using a
variable bit rate coding, even if information data which has
undergone editing such as chapter setting, erasure or the like
after recording is reproduced from a midway position, time
information on reproduction at that position can be derived.
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